我需要super.super.method()->可能的设计缺陷？ - java

我发现自己需要在java中调用super.super.method()，这是不可能的。

我只是想知道我的设计中是否存在设计缺陷？

这些课程:

package solvers.command;

/**
 *
 * @author student
 */
public abstract class Command {
    private boolean executed;   //executed state

    /**
     * Constructs a new Command object.
     * 
     * @modifies    this.executed = false
     */
    public Command() {
        this.executed = false;
    }

    /**
     * Executes this command.
     * 
     * @modifies executed = true
     * @pre {@code !executed}
     * @throws IllegalStateException if {@code executed}
     */
    public void execute() {
        if (executed) {
            throw new IllegalStateException("solvers.command.Command.execute: already executed");
        }
        executed = true;
    }

    /**
     * Undoes this command.
     * 
     * @modifies executed = false
     * @pre {@code executed}
     * @throws IllegalStateException if {@code !executed}
     */
    public void undo() {
        if (!executed) {
            throw new IllegalStateException("solvers.command.Command.undo: not executed yet");
        }
        executed = false;
    }

    /**
     * Returns the executed state
     * 
     * @return executed state
     */
    public boolean getExecuted() {
        return executed;
    }
}

package solvers.command;

import java.util.ArrayList;
import java.util.Collections;
import java.util.List;

/**
 *
 * @author student
 */
public class CompoundCommand extends Command {
    List<Command> commands; //list of commands

    /**
     * Creates a new CompoundCommand.
     * 
     * @modifies this.commands is initialised
     */
    public CompoundCommand() {
        super();
        this.commands = new ArrayList<>();
    }

    /**
     * Adds a command to the list of commands.
     * 
     * @param command   The new command
     * @pre {@code command != null}
     * @throws IllegalArgumentException if {@code command == null}
     */
    public void add(final Command command) {
        if (command == null) {
            throw new IllegalArgumentException("solvers.command.CompoundCommand.add: "
                    + "command == null");
        }
        commands.add(command);
    }

    /**
     * Removes a command from the list of commands.
     * 
     * @param command   The command to be removed
     * @pre {@code command != null && commands.contains(command}
     * @throws IllegalArgumentException if {@code command == null || !commands.contains(command)}
     */
    public void remove(final Command command) {
        if (command == null) {
            throw new IllegalArgumentException("solvers.command.CompoundCommand.remove: "
                    + "command == null");
        }
        if (!commands.contains(command)) {
            throw new IllegalArgumentException("solvers.command.CompoundCommand.remove:"
                    + "command is not found in commands");
        }
        commands.remove(command);
    }

    /**
     * Returns if the list of commands is empty.
     * 
     * @return {@code commands.isEmpty()}
     */
    public boolean isEmpty() {
        return commands.isEmpty();
    }

    @Override
    public void execute() {
        super.execute();
        for (Command c : commands) {
            c.execute();
        }
    }

    @Override
    public void undo() {
        super.undo();
        Collections.reverse(commands);
        for (Command c : commands) {
            c.undo();
        }
        Collections.reverse(commands);
    }
}

package solvers.command;

/**
 *
 * @author student
 */
public class ExecutedCompoundCommand extends CompoundCommand {

    /**
     * Creates a new ExecutedCompoundCommand.
     */
    public ExecutedCompoundCommand() {
        super();
    }

    @Override
    public void add(final Command command) {
        if (!command.getExecuted()) {
            throw new IllegalStateException("solvers.command.ExecutedCompoundCommand.add: "
                    + "command has not been executed yet.");
        }
        super.add(command);
    }

    @Override
    public void execute() {
        super.super.execute(); /* Does not work obviously */
        for (Command c : commands) {
            if (!c.getExecuted()) {
                c.execute();
            }
        }
    }
}

基本上，我确实想要命令的execute()的安全性，而我不想为CompoundCommand实现ExecutedCompoundCommand的execute()，但我确实希望仅依赖于的add()，remove()和undo()操作CompoundCommand。

作为一个学生，在使用必需的Javadoc和单元测试进行项目时，确实需要尽可能减少代码重复，因为这样做只会使工作更多。

参考方案

我认为这是设计缺陷。您可以应用模板方法模式[GOF 325]

目的:根据操作定义算法的框架
子类的一些步骤。模板方法可让子类重新定义
算法的某些步骤而无需更改算法的
结构体。

从四个设计模式的帮派

您要确保执行某些步骤。因此，您需要使最终的模板方法execute()并委托给doExecute()方法，该方法可以添加其他逻辑，并且需要由子类实现。

public final void execute() {
  importantOperation();
  runsAlways();
  doExecute();
}

public abstract void doExecute(); // Override in subclasses

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